In previous research on "Speech Accommodations by and to Older Adults" using a referential communication task, young adults adjusted their fluency, semantic content, and syntactic complexity to the perceived communication needs of their partners. Older adults did not make such speech adjustments and appeared to use a consistent speech style in a variety of situations, suggesting, like other lines of research, that older adults' speech production is constrained by working memory limitations that affect their production of complex syntactic constructions. The present proposal will extend this study of older adults' speech accommodations by using "on-line" experimental tasks manipulated the working memory demands of sentence production tasks. Three series of experiments are proposed. Series 1 will analyze language samples to assess the effects on concurrent processing demands on linguistic fluency, syntactic complexity, and semantic content. A baseline language sample will be compared to language samples collected while participants are concurrently walking, tapping their index fingers, tapping four fingers in a complex pattern, listening to concurrent speech, and listening to auditory babble. These concurrent tasks have previously been shown to affect performance on working memory tasks, hence, they are predicted to compete for working memory and, in turn affect speech production. Walking and tapping rates will also be examined in baseline and concurrent speaking conditions. Series 2 will use a sentence production task that controls the choice of lexical items and examines the latency to generate a sentence using a specified set of lexical items and the complexity of the generated sentence. Three experiments are planned: (2a) To examine sentence initiation times and sentence complexity as a function of the size of the set of specified lexical items. (2b) To examine sentence initiation times and sentence complexity for sentences generated from single verbs or for sentences generated from multiple verbs. (2c) To examine sentence initiation times and sentence complexity for sentences generated to complete simple and complex sentence frames using a specified inventory of lexical items. Series 3 will use a controlled sentence production task that examines the latency to initiate memorized sentences. Three experiments are planned: (3a) To examine sentence initiation times for simple and complex sentences. (3b) To examine intra-sentence pauses during the production of simple and complex sentences. (3c) To examine sentence initiation times for semantically constrained and reversible sentences. In all three series of experiments, individual differences in verbal ability, processing speed, working memory, and inhibition will also be examined.